Stillman & Birn Gamma Series Archival Sketchbooks are available in both hardbound and wirebound formats. They contain multiple sheets of 180 lb (270 gsm) ivory paper with a medium grain surface, and enhanced wet strength and tear strength.

Gamma Series
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Available in both hardbound and wirebound formats, these sketchbooks contain multiple sheets of 100 lb (150 gsm), ivory paper with a vellum surface and a distinctive tooth. Ideal for dry media and light washes, the paper is both internally sized and surface-sized. The hardbound sketchbooks contain 62 sheets (124 pages) of paper. The wirebound sketchbooks contain 50 sheets (100 pages) of paper.